This invention relates to multi-purpose photographic film cassettes of the type in which a film strip is initially packaged for retention without removal during exposure, processing and projection operations. More particularly, it concerns a novel organization for absorbing residual processing fluid applied to the film strip during rewind through an applicator nozzle sealed or closed at the termination of film strip processing.
Cinematographic systems employing a multi-purpose film cassette containing a photographic film strip together with a supply of processing fluid so that the film strip may be exposed in a camera and subsequently processed and projected in an appropriate viewing apparatus exclusively by manipulation of the cassette alone are the subject of several pending and issued U.S. patents commonly assigned to the assignee of the present invention. A recent development of the viewing apparatus for such systems is exemplified by a copending application, Ser. No. 756,542, filed by Herbert L. Hardy on Jan. 3, 1977. In such systems, after the film strip is exposed by mounting the cassette in a motion picture camera, the cassette is inserted into an automatic viewing apparatus capable of discerning the processed or unprocessed condition of the film strip and in the latter case, initiating a processing mode of operation. During processing, the viewing apparatus operates to rewind the film strip from a cassette contained take-up spool back to a supply spool under a processing fluid applicator having a nozzle through which processing fluid flows by gravity and is spread evenly over the emulsion side of the film strip. At the end of processing, a cassette contained valve member is moved to a position closing the processing fluid nozzle to prevent further discharge of any residual processing fluid from the applicator.
The problem of handling residual fluid in the above-noted applicator has been recognized and dealt with in such prior disclosures as those of U.S. Pat. No. 3,806,237 issued Apr. 23, 1974 to Edwin H. Land; U.S. Pat. No. 3,868,716 issued Feb. 25, 1975 to Irving S. Lippert and Joseph A. Stella; and U.S. Pat. No. 3,882,526 issued May 6, 1975 to Irving S. Lippert and Joseph A. Stella, each such patents being commonly assigned with the present invention. In U.S. Pat. No. 3,882,526, for example, the processor is internally fitted with a time delay, absorbent sponge or foam to be exposed within the pod or reservoir of processing fluid to retain any residual amounts of such fluid after processing. In U.S. Pat. No. 3,868,716, a pad of sealant material is also provided on the valve member and carried by the latter to the nozzle of the processor at the termination of the processing operation to seal the nozzle against passage of any residual processing fluid.
Additionally, an arrangement for repeatedly cleaning film engaging components has been disclosed in the commonly assigned U.S. Pat. No. 3,806,237 wherein a cleaning pad carried by the film strip is advanced across critical components of the viewer during each projection cycle of the viewer apparatus.
While the above-noted systems are quite satisfactory for viewer apparatus where the fluid deposit is uniform, further difficulty arises in systems such as described in the aforementioned application Ser. No. 756,542 wherein the film speed is slowed down at the end of processing. In the latter case, since the aforementioned slide valve is picked up and closed by the slowly moving film and also deflects a film support member away from the film, thereby allowing slight displacement of the latter from the nozzle, a relatively large amount of fluid is deposited on the film at this time, thereby causing a fluid puddle. The fluid thus remaining as a puddle on the film will require an unacceptable drying time and be carried by the film strip as liquid in a manner to represent a potential source of cassette component fouling when the film strip is taken through a mandatory project cycle following the processing operation. Thus, enhanced overall system operation will result where complete disposition of all residual processing fluid is accounted for.